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[RFC 5/9] RISC-V: Add SBI PMU snapshot definitions

Atish Patra posted 9 patches 2 years ago
There is a newer version of this series
[RFC 5/9] RISC-V: Add SBI PMU snapshot definitions
Posted by Atish Patra 2 years ago 
SBI PMU Snapshot function optimizes the number of traps to
higher privilege mode by leveraging a shared memory between the S/VS-mode
and the M/HS mode. Add the definitions for that extension

Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
 arch/riscv/include/asm/sbi.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index f3eeca79a02d..29821addb9b7 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -122,6 +122,7 @@ enum sbi_ext_pmu_fid {
 	SBI_EXT_PMU_COUNTER_STOP,
 	SBI_EXT_PMU_COUNTER_FW_READ,
 	SBI_EXT_PMU_COUNTER_FW_READ_HI,
+	SBI_EXT_PMU_SNAPSHOT_SET_SHMEM,
 };
 
 union sbi_pmu_ctr_info {
@@ -138,6 +139,13 @@ union sbi_pmu_ctr_info {
 	};
 };
 
+/* Data structure to contain the pmu snapshot data */
+struct riscv_pmu_snapshot_data {
+	uint64_t ctr_overflow_mask;
+	uint64_t ctr_values[64];
+	uint64_t reserved[447];
+};
+
 #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
 #define RISCV_PMU_RAW_EVENT_IDX 0x20000
 
@@ -234,9 +242,11 @@ enum sbi_pmu_ctr_type {
 
 /* Flags defined for counter start function */
 #define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
+#define SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT (1 << 1)
 
 /* Flags defined for counter stop function */
 #define SBI_PMU_STOP_FLAG_RESET (1 << 0)
+#define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT (1 << 1)
 
 enum sbi_ext_dbcn_fid {
 	SBI_EXT_DBCN_CONSOLE_WRITE = 0,
-- 
2.34.1
Re: [RFC 5/9] RISC-V: Add SBI PMU snapshot definitions
Posted by Anup Patel 2 years ago 
On Tue, Dec 5, 2023 at 8:13 AM Atish Patra <atishp@rivosinc.com> wrote:
>
> SBI PMU Snapshot function optimizes the number of traps to
> higher privilege mode by leveraging a shared memory between the S/VS-mode
> and the M/HS mode. Add the definitions for that extension
>
> Signed-off-by: Atish Patra <atishp@rivosinc.com>

LGTM.

Reviewed-by: Anup Patel <anup@brainfault.org>

Regards,
Anup

> ---
>  arch/riscv/include/asm/sbi.h | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> index f3eeca79a02d..29821addb9b7 100644
> --- a/arch/riscv/include/asm/sbi.h
> +++ b/arch/riscv/include/asm/sbi.h
> @@ -122,6 +122,7 @@ enum sbi_ext_pmu_fid {
>         SBI_EXT_PMU_COUNTER_STOP,
>         SBI_EXT_PMU_COUNTER_FW_READ,
>         SBI_EXT_PMU_COUNTER_FW_READ_HI,
> +       SBI_EXT_PMU_SNAPSHOT_SET_SHMEM,
>  };
>
>  union sbi_pmu_ctr_info {
> @@ -138,6 +139,13 @@ union sbi_pmu_ctr_info {
>         };
>  };
>
> +/* Data structure to contain the pmu snapshot data */
> +struct riscv_pmu_snapshot_data {
> +       uint64_t ctr_overflow_mask;
> +       uint64_t ctr_values[64];
> +       uint64_t reserved[447];
> +};
> +
>  #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
>  #define RISCV_PMU_RAW_EVENT_IDX 0x20000
>
> @@ -234,9 +242,11 @@ enum sbi_pmu_ctr_type {
>
>  /* Flags defined for counter start function */
>  #define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
> +#define SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT (1 << 1)
>
>  /* Flags defined for counter stop function */
>  #define SBI_PMU_STOP_FLAG_RESET (1 << 0)
> +#define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT (1 << 1)
>
>  enum sbi_ext_dbcn_fid {
>         SBI_EXT_DBCN_CONSOLE_WRITE = 0,
> --
> 2.34.1
>
Re: [RFC 5/9] RISC-V: Add SBI PMU snapshot definitions
Posted by Conor Dooley 2 years ago 
On Mon, Dec 04, 2023 at 06:43:06PM -0800, Atish Patra wrote:
> SBI PMU Snapshot function optimizes the number of traps to
> higher privilege mode by leveraging a shared memory between the S/VS-mode
> and the M/HS mode. Add the definitions for that extension
> 
> Signed-off-by: Atish Patra <atishp@rivosinc.com>
> ---
>  arch/riscv/include/asm/sbi.h | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> index f3eeca79a02d..29821addb9b7 100644
> --- a/arch/riscv/include/asm/sbi.h
> +++ b/arch/riscv/include/asm/sbi.h
> @@ -122,6 +122,7 @@ enum sbi_ext_pmu_fid {
>  	SBI_EXT_PMU_COUNTER_STOP,
>  	SBI_EXT_PMU_COUNTER_FW_READ,
>  	SBI_EXT_PMU_COUNTER_FW_READ_HI,
> +	SBI_EXT_PMU_SNAPSHOT_SET_SHMEM,
>  };
>  
>  union sbi_pmu_ctr_info {
> @@ -138,6 +139,13 @@ union sbi_pmu_ctr_info {
>  	};
>  };
>  
> +/* Data structure to contain the pmu snapshot data */
> +struct riscv_pmu_snapshot_data {
> +	uint64_t ctr_overflow_mask;
> +	uint64_t ctr_values[64];
> +	uint64_t reserved[447];
> +};
> +
>  #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
>  #define RISCV_PMU_RAW_EVENT_IDX 0x20000
>  
> @@ -234,9 +242,11 @@ enum sbi_pmu_ctr_type {
>  
>  /* Flags defined for counter start function */
>  #define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
> +#define SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT (1 << 1)
>  
>  /* Flags defined for counter stop function */
>  #define SBI_PMU_STOP_FLAG_RESET (1 << 0)
> +#define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT (1 << 1)

If we can use GENMASK in this file, why can we not use BIT()?

>  
>  enum sbi_ext_dbcn_fid {
>  	SBI_EXT_DBCN_CONSOLE_WRITE = 0,
> -- 
> 2.34.1
>
Re: [RFC 5/9] RISC-V: Add SBI PMU snapshot definitions
Posted by Atish Patra 2 years ago 
On Thu, Dec 7, 2023 at 4:34 AM Conor Dooley <conor.dooley@microchip.com> wrote:
>
> On Mon, Dec 04, 2023 at 06:43:06PM -0800, Atish Patra wrote:
> > SBI PMU Snapshot function optimizes the number of traps to
> > higher privilege mode by leveraging a shared memory between the S/VS-mode
> > and the M/HS mode. Add the definitions for that extension
> >
> > Signed-off-by: Atish Patra <atishp@rivosinc.com>
> > ---
> >  arch/riscv/include/asm/sbi.h | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> >
> > diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> > index f3eeca79a02d..29821addb9b7 100644
> > --- a/arch/riscv/include/asm/sbi.h
> > +++ b/arch/riscv/include/asm/sbi.h
> > @@ -122,6 +122,7 @@ enum sbi_ext_pmu_fid {
> >       SBI_EXT_PMU_COUNTER_STOP,
> >       SBI_EXT_PMU_COUNTER_FW_READ,
> >       SBI_EXT_PMU_COUNTER_FW_READ_HI,
> > +     SBI_EXT_PMU_SNAPSHOT_SET_SHMEM,
> >  };
> >
> >  union sbi_pmu_ctr_info {
> > @@ -138,6 +139,13 @@ union sbi_pmu_ctr_info {
> >       };
> >  };
> >
> > +/* Data structure to contain the pmu snapshot data */
> > +struct riscv_pmu_snapshot_data {
> > +     uint64_t ctr_overflow_mask;
> > +     uint64_t ctr_values[64];
> > +     uint64_t reserved[447];
> > +};
> > +
> >  #define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(47, 0)
> >  #define RISCV_PMU_RAW_EVENT_IDX 0x20000
> >
> > @@ -234,9 +242,11 @@ enum sbi_pmu_ctr_type {
> >
> >  /* Flags defined for counter start function */
> >  #define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
> > +#define SBI_PMU_START_FLAG_INIT_FROM_SNAPSHOT (1 << 1)
> >
> >  /* Flags defined for counter stop function */
> >  #define SBI_PMU_STOP_FLAG_RESET (1 << 0)
> > +#define SBI_PMU_STOP_FLAG_TAKE_SNAPSHOT (1 << 1)
>
> If we can use GENMASK in this file, why can we not use BIT()?
>

Sure. Done. I will change the other ones in a separate patch as well.

> >
> >  enum sbi_ext_dbcn_fid {
> >       SBI_EXT_DBCN_CONSOLE_WRITE = 0,
> > --
> > 2.34.1
> >



-- 
Regards,
Atish

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